Bathtub mat



FIG. 1 is a top view of the bathtub mat is accordance with my invention;

FIG. 2 is a bottom view thereof;

FIG. 3 is a left side view thereof;

FIG. 4 is a right side view thereof;

FIG. 5 is an upper end view thereof; and,

FIG. 6 is a lower end view thereof.

The broken lines shown in FIGS. 1-6 are for illustrative purposes only and form no part of the claimed design. 

The ornamental design for a bathtub mat, as shown and described herein. 